Rep. Chris Van Hollen, a Democrat from Kensington, has been elected to fill Sen. Barbara Mikulski's vacated Senate seat in January. Mikulski is retiring after 30 years in office.

Van Hollen secured 61 percent of the vote, beating out Republican state Del. Kathy Szeliga, the minority whip of Maryland's House of Delegates, who earned nearly 36 percent of the vote.

"We are a microcosm of our country, and I look forward to working with each and every one of you to bring Marylanders together as we bring Americans together," Van Hollen said at a watch party in Silver Spring Tuesday night.

A seasoned politician from the state of Maryland's 8th District, Van Hollen was favored to win after holding a comfortable double-digit lead over Szeliga throughout the election season. An October poll by The University of Maryland and The Washington Post showed Van Hollen led Szeliga among likely voters 58 to 29 percent.

Some students at this university cast their votes Tuesday in Stamp Student Union. Of the 1,313 Senate votes, roughly 82 percent, or 1,074 people, voted for Van Hollen. About 18 percent – 239 people – voted for Szeliga, according to an election judge.

Van Hollen had defeated 4th District Rep. Donna Edwards for the Democratic nomination by more than 10 percent during the April primary election following a heated race that was nearly neck-in-neck for most of the primary season.

The congressman, who has been serving since 2003, focused his campaign on fixing the economy, expanding education and ending gun violence. He proposed creating financial incentives to create handgun licensing programs, which this state passed in 2013. Van Hollen has spent his career in the House fighting for the Affordable Care Act and working to pass budget reform as a ranking Democrat on the House Budget Committee.

In his acceptance speech, Van Hollen also noted the importance of "end[ing] the scandal of mass incarceration," along with giving all children the opportunity to have an affordable education and addressing climate change.

"We can do these things together, but we also need to recognize that this election has been different from other elections … in this election, we have had the character of America at stake," he said.

Yvette Lewis, the chairwoman of the Maryland Democratic Party, celebrated the congressman's victory.

"What an exciting night this is where we can finally call him Sen. Chris Van Hollen," Lewis said.

The Van Hollen campaign, which touted numerous endorsements including from Minority Leader Harry Reid, Maryland Attorney General Brian Frosh and the Baltimore Sun, raised more than $9.57 million during this election season, according to FEC filings. Donations from individuals at this university made up more than $46,000 of the Van Hollen campaign's contributions — the second highest of all his contributors, according to the Center for Responsive Politics.

Szeliga's campaign, which raised a little more than $1.4 million, according to FEC filings, grilled Van Hollen on the role of money in politics, arguing that throughout his career he has taken money from lobbyist and lawyers.

"My opponent has raised hundreds of millions of dollars and he is beholden to special interest groups," Szeliga said in a previous October interview. "He claims to be a champion for veterans, well you heard the Veteran's Administration is failing day after day. He won't even say we need to balance the budget, which means he's putting more money on the credit card of your future."

Van Hollen acknowledged Szeliga, who called him after the results were finalized, at the watch party.

"I want to thank Delegate Szeliga … let's give her a round of applause," he said. "I want to commend her on putting her ideas and her platform forward."

Despite facing a loss, Szeliga said she would not give up and would continue to pursue her ideas.

"I'm going to continue to fight for you, continue to carry the banner for us and our ideas," Szeliga told supporters Tuesday night, according to The Baltimore Sun. "This was never about me. This was about Maryland and carrying forward our values."

Staff writer Alex Carolan contributed to this report.