BATON ROUGE, La. (AP) — Republican U.S. Sen. Bill Cassidy was trying to reach a high hurdle Tuesday in Louisiana's election, seeking to defeat 14 challengers in the primary without needing to continue his campaign through a December runoff.

To reach a second term without another month of campaigning, Cassidy would need to take more than 50% of the vote outright, which his campaign and some analysts believe is possible for the GOP incumbent in a red state.

Also on Louisiana's ballot were six U.S. House races, seven constitutional amendments and a parish-by-parish decision on whether to legalize sports betting. Polls close at 8 p.m.

Only a handful of Cassidy's opponents actively campaigned to win the position. Most of the high-profile Democratic endorsements and campaign donations went to Shreveport Mayor Adrian Perkins, 35.

Cassidy, a 63-year-old doctor from Baton Rouge, raised millions to blanket the airwaves with advertising and held higher name recognition than his challengers. He also received the backing of President Donald Trump.

Democrats hope that if Perkins and other candidates could peel off enough votes to force Cassidy into a runoff, a head-to-head matchup could change the race's dynamics and make Cassidy more vulnerable to defeat.

Cassidy focused much of his campaign on TV and social media advertising. He avoided large events, his campaign citing the coronavirus pandemic. In August, Cassidy contracted COVID-19 and had mild symptoms.

The Republican incumbent ran campaign ads panning Democratic presidential candidate Joe Biden, touting his support for Trump's Supreme Court pick Amy Coney Barrett and talking of his work on health care issues. He posted social media clips tying support for his reelection bid to backing of Trump. And he promoted his medical background, including his long-time work at the state's charity hospital system.

“If the problems that confront our society now are ‘What do we do about health care? What do we do about public health? What do we do about energy policy knowing that it’s an incredible driver of jobs,’ I feel like that my background of working in public health, in health care and in a state in which jobs are such closely linked to the energy economy prepares me extremely well," Cassidy said in one interview.

He refused to participate in debates that did not include invites to all 14 of his opponents — so no debates were held for the first time in a Louisiana U.S. Senate race since 1998.

Perkins, Democratic candidate Antoine Pierce and others criticized Cassidy's votes to repeal the Affordable Care Act. They accused Cassidy and Senate Republicans of blocking needed COVID-19 aid in a partisan feud with the Democratic-led U.S. House. And they panned Cassidy as siding with Trump, the GOP and corporations over his poor state's own interests.

But Perkins was the only challenger to have enough money for widespread TV advertising. Democrats talked of the Shreveport mayor's impressive resume, with a West Point education, a Harvard law degree and military service in Iraq and Afghanistan. Perkins received endorsements from former President Barack Obama and Louisiana Gov. John Bel Edwards.

Perkins described being raised by a single mother who worked multiple jobs and sometimes skipped her own meals to ensure her children were fed. He said that experience would help him understand the struggles of Louisiana families, particularly in the economic hit of the pandemic.

“If we give (Cassidy) another six years in office, he will continue to come after our health care. He will continue to cozy up to the corporations that have paid him over $6 million,” Perkins said at a candidate forum that Cassidy skipped.

Perkins, however, had far less money to hammer Cassidy on his record on the airwaves. He raised nearly $1.8 million to Cassidy’s $10.9 million, according to reports filed with the Federal Election Commission.

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Follow Melinda Deslatte on Twitter at http://twitter.com/melindadeslatte.

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