David Jackson

USA TODAY

COUNCIL BLUFFS, Iowa — Donald Trump exuded confidence the day before his first election day, urging supporters Sunday to caucus for him and even talking about the criteria for a vice president. "We're going to win, we're going to win," Trump told an enthusiastic crowd in a middle school gym. "We're leading everywhere."

Asked what he might be looking for in a running mate, Trump first said it was too early to discuss the subject, though he went on to say he would consider people in key election states and pick a person who could assume the presidency if necessary. "There are some great people out there," Trump said.

The New York businessman who has never sought public office appears to be locked in a tight battle with Texas Sen. Ted Cruz a day ahead of the Iowa caucuses. Kicking off a brief Sunday swing in western Iowa, Trump provided a litany of the protests with the current government have have fueled his campaign: jobs, trade deals, the Iran nuclear agreement, the Syrian refugee problems, and the battle against the Islamic State. "What's going on is so sad and the decisions are so sad," Trump said at one point.

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Having covered cities in eastern Iowa on Saturday, Trump devoted Sunday to television appearances and to events in the more conservative, more religious communities in western Iowa. He was accompanied by prominent religious conservative Jerry Falwell Jr., president of Liberty University.

After the event in Council Bluffs, Trump traveled to Sioux City for an evening rally. On caucus day itself Monday, Trump is scheduled to be back east with rallies in Waterloo and Cedar Rapids. Trump did not give a speech at Council Bluffs. He instead sat for an "interview" with Falwell, a format that drew a few complaints from the crowd. "Stand up!" one man shouted. "We can't see you!"

Another new feature of Trump rallies: presenting a check to veterans, proceeds from the event he held Thursday after opting to boycott a Republican debate. On Sunday, a $100,000 check went to an organization that trains service dogs for disabled veterans.

Trump drew applause when he mentioned the debate boycott, saying the sponsors at Fox News have been unfair to him. Cruz criticized Trump's absence from the debate, saying CNN's State of the Union that Trump as telling the people of Iowa that "he wasn't willing to submit to the scrutiny" of his record.

Cruz, backed by many of the state's evangelical leaders, said he has faith in his Iowa organization and attributed Trump's constant attacks on him to the fact the polls are close. "A month ago, Donald was telling everyone how much he liked me and how much I was his friend," Cruz told CNN. "And then his poll numbers started falling, and ours started rising. And now I wake up every day and look at my phone and discover what new insult he has launched out."

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Members of the crowd wore apparel reflecting the Trump message, including T-shirts that said "Made In America" and, of course, the campaign slogan "Make America Great Again."

Iowans who attended the Council Bluffs event reflected their candidate's optimism, saying a Trump win in their state should send him on to the nomination.

"A lot of people are after him," said Kathy Simpson, 62, of Glenwood, Iowa. "But he's confident. I'm confident."

Some Trump backers came from other states to catch him in Council Bluffs. Kim Dye, 47, who with husband Charles made a four-and-a-half hour drive from Wichita, Kan., wore a blue "Make America Great" hat as she said the businessman would "get us back on track economically and socially."

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Shelly Stark, 56, who lives in Omaha but said she has friends and family voting in Iowa, said she likes Trump for his stance against illegal immigration, which she described as an invasion. "If they are here illegally, I really do think it's an invasion," said Stark, a production manager for a stage company.

Her shirt read: "It's a Trump thing — you wouldn't understand."