Democratic Rep. Gabrielle Giffords of Arizona was shot in the head during a constituent event outside a supermarket in Tucson. She resigned from the House and has since worked for gun control through the Giffords Law Center. In 2020, former astronaut Mark Kelly, Giffords husband, won the Senate seat held by Republican John McCain. Arizona now has two Democratic senators.

[Pictured: Former U.S. Rep. Gabrielle Giffords (L) is escorted by Rep. Debbie Wasserman Schultz after she resigned from the House of Representatives on Capitol Hill on Jan. 25, 2012.]

President Barack Obama won a second term against former Massachusetts Gov. Mitt Romney. He took the popular vote 51.1% to 47.2% and got 332 electoral votes. Romney received 206 electoral votes. Obama won among women, African Americans, and Latinos, and lost among white men.

[Pictured: President Barack Obama stands on stage with First Lady Michelle Obama after his victory speech at McCormick Place in Chicago.]

President Barack Obama tried to explain why the African American community was so upset about the acquittal of the killer of Trayvon Martin, the 17-year-old Black teenager shot in Sanford, Florida, as he returned to his father’s fiance’s townhouse from a convenience store. George Zimmerman, a neighborhood watch volunteer, was acquitted on a second-degree murder charge. “Trayvon Martin could have been me 35 years ago,” Obama said.

[Pictured: President Barack Obama speaks on the Trayvon Martin case during remarks in the White House briefing room July 19, 2013.]

President Barack Obama advanced protections for LGBT workers. His executive order forbids federal contractors from discriminating against LGBT employees, adding sexual orientation and gender identity to an order issued by former President Lyndon Johnson.

[Pictured: President Obama signs an executive order to protect LGBT employees from workplace discrimination on July 21, 2014.]

President Barack Obama and the Environmental Protection Agency created the Clean Power Plan to address the effects of climate change. The plan was intended to reduce carbon pollution from power plants, the country’s largest source of carbon, by more than 30% by 2030. President Donald Trump rolled back the plan, replacing it with one that lets states set their own rules.

[Pictured: President Obama speaks at Sempra U.S. Gas & Power's Copper Mountain Solar 1 facility, the largest photovoltaic solar plant in the U.S., on March 21, 2012, in Boulder City, Nevada.]

Hillary Clinton became the first woman to win the presidential nomination of a major American political party. As the Democrats’ candidate, she lost to Donald Trump, making his first run for any political office. The race was bitter, Russians hacked emails from her presidential campaign and the Democratic National Committee, and although Trump got 2.8 million fewer popular votes, he won the Electoral College 304 to 227 for the former secretary of state and first lady.

[Pictured: Hillary Clinton acknowledges the crowd at the end on the fourth day of the Democratic National Convention at the Wells Fargo Center, July 28, 2016, in Philadelphia.]

California’s Democratic Attorney General Xavier Becerra sued the Trump administration 24 times in 2017 over a range of disputes, from immigration to climate change. By August 2020, California sued over his policies 100 times, including over California’s ability to set its own standards on vehicle emissions.

Democrats received more information about how Russians had worked against them in the 2016 election when the Department of Justice charged 13 Russians and three companies in an indictment that involved Russians posing as political activists and stirring up disputes on immigration and race. President Donald Trump tweeted that his campaign had done nothing wrong. The DOJ later moved to drop charges against two of the companies, saying they were using the legal system to obtain information.

[Pictured: Former Special Counsel Robert Mueller testifies before the House Intelligence Committee about his report on Russian interference in the 2016 presidential election on July 24, 2019.]

The Democratic-led House of Representatives voted to impeach President Donald Trump on charges of abuse of power and obstruction of Congress. The president was accused of trying to pressure Ukraine to conduct investigations to discredit former Vice President Joe Biden, his likely rival in 2020. Trump became the third president to be impeached. He was acquitted the next year by the Republican-controlled Senate.

[Pictured: Speaker of the House Nancy Pelosi gavels the close of a vote by the U.S. House of Representatives on a resolution formalizing the impeachment inquiry centered on President Trump, Oct. 31, 2019.]

Former Democratic Vice President Joe Biden beat President Trump in a historic election that saw the country choose the first Black woman and first Asian American woman as vice president. The election took place in the midst of the coronavirus pandemic. The days after President-elect Biden’s victory were unprecedented as Trump refused to concede and repeatedly challenged the result in court, unsuccessfully. President-elect Biden won 306 electoral votes to Trump’s 232.

[Pictured: President-elect Joe Biden speaks at the Queen Theater in Wilmington, Delaware, on Nov. 10, 2020]

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