(NewsNation) — Republican presidential candidates held a series of campaign events Friday in Iowa as the battle to become former President Donald Trump’s nearest rival reaches a fever pitch.

Former South Carolina Gov. Nikki Haley, Florida Gov. Ron DeSantis and entrepreneur Vivek Ramaswamy took their message to the Family Leader’s Thanksgiving forum in Des Moines, courting the Christian conservative vote.

With just two months to go before the critical first-in-the-nation caucuses, Iowa is very much back in focus for these GOP candidates who crisscrossed the state before the forum, courting last-minute votes.

DeSantis has long been considered the party’s top challenger to Trump, who has held on to a significant lead over the rest of the field — but momentum from standout debate performances has appeared to boost Haley, raising questions about which challenger will secure the second-place slot in Iowa.

Haley and DeSantis are most recently tied in polls for second place in the Hawkeye State.

DeSantis touts a big endorsement from Iowa Gov. Kim Reynolds, while Haley picked up dozens of prominent endorsements as well.

Haley’s team also announced it plans to spend $10 million on ads, both radio TV digital ads in Iowa and New Hampshire.

As their competition for second place heats up, Haley and DeSantis have been clashing on the debate stage and in mailers, online posts and media appearances.

The two have lobbed claims at each other in recent weeks on dealings with Chinese companies and energy.

DeSantis in particular has ramped up the attacks, the New York Times reports, seeking to use Haley’s own appeal to a broader coalition of voters against her by casting her as too liberal.

“Iowa is the first and best shot Govs. Haley and DeSantis will have to emerge as the clear alternative to President Trump,” said Michael Zona, a Republican strategist and former staffer for Iowa Republican Sen. Chuck Grassley.