Speaking from the student union at the Ohio State University in Columbus, Gov. John Kasich announced that he is seeking the Republican nomination for president in 2016. (AP)

Ohio Gov. John Kasich joined the crowded 2016 GOP presidential race Tuesday, offering an optimistic message that blends fiscal conservatism with social welfare compassion that he hopes will shake up the Republican Party and vault him into contention for the nomination.

“I am here to ask you for your prayers, for your support, for your efforts, because I have decided to run for president of the United States,” the two-term governor told a cheering crowd at a rally at the Ohio State University.

Kasich’s speech was short on policy proposals, with almost no discussion of foreign affairs. Instead, it was long on biography and inspirational rhetoric, characteristics that Kasich hopes will peg him as a candidate with a style, message and priorities that distinguish him from his rivals.

To those who consider him a long-shot candidate, Kasich recounted other times when he has been underestimated, as a candidate and an elected official. “They said it couldn’t be done but we proved them wrong,” he said repeatedly, as if to encourage his supporters to have confidence that he can do so again in the presidential race.

He spoke of family and faith, of those left behind and those who wonder if the American dream is still alive. “If we’re not born to serve others, what were we born to do?” he said.

The weekend before he was expected to announce his run for president, Ohio Gov. John Kasich's political committee released an ad discussing the other candidates in the 2016 race. (New Day for America)

He highlighted his record in Ohio of putting his state on a sounder financial footing and boosting its long-struggling economy. “We are going to take the lessons of the heartland and straighten out Washington, D.C.,” he said.

Kasich begins the contest far back in the field. His advisers say they think he can become a credible threat to win the nomination by force of personality and record. His detractors question whether he has the discipline required for a long and grueling presidential race.

Displaying his trademark self-confidence, Kasich said he was not daunted by what could lie ahead. “When I’m president, I know what we need to do,” he said. “There’s no confusion about that. I know.”

Kasich’s entry rounds out the largest Republican presidential field in modern memory, with at least 16 candidates seeking the nomination. Collectively, the 2016 GOP field is more experienced and politically heftier than those who sought the nomination four years ago.

That, at least, is the way it looked on paper as the competition began. So far, however, none of the candidates has truly broken out or broken through, save for businessman Donald Trump, who has dominated the contest since his entry last month. No one, including former Florida governor Jeb Bush — the son and brother of presidents who has amassed in excess of $110 million for his campaign and super PAC — has been able to come close to taking charge.

Since becoming a candidate, Trump has found an audience with harsh attacks on illegal immigration and illegal immigrants. A new Washington Post-ABC News poll showed the real estate mogul leading the others in the race, with 24 percent support.

But Trump also has generated much controversy, the latest coming last weekend when he appeared to disparage Sen. John McCain (R-Ariz.) as not being a hero just because he was held prisoner during the Vietnam War. There were hints in the Post-ABC News poll that his comments about McCain have begun to affect his numbers.

The Post's Dan Balz shares his Snapchats from the presidential campaign launch for Ohio Gov. John Kasich (R). (Dan Balz/The Washington Post)

Who will emerge as finalists in the GOP competition remains a matter of debate and conjecture. Beyond Bush, the names most often cited as possible long-distance runners are Wisconsin Gov. Scott Walker, who is in second place in the Post-ABC News poll and leads surveys in Iowa, and Sen. Marco Rubio (Fla.), who argues that he would contrast favorably against Hillary Rodham Clinton, the Democratic front-runner, in a general election.

At this point, two races are underway. One is a contest among some of the most conservative candidates for supremacy in Iowa. The other is a largely separate contest among those candidates considered less conservative who will need a strong finish in New Hampshire to stay alive.

It is the New Hampshire contest that is most attractive to Kasich, who will spend several days there this week campaigning.

Kasich, 63, served in the House for 18 years. He sat on the Armed Services Committee and was chairman of the Budget Committee, helping to lead a successful effort to balance the federal budget. He ran for president in 2000 but was an early casualty. He spent a decade in business and television before winning the governorship in 2010 in a state that often helps decide presidential elections. He won reelection in a landslide last November.

In Ohio, he cut taxes and eliminated a sizable budget deficit. To the chagrin of conservatives, he engineered an expansion of Medicaid under the Affordable Care Act. He called for spending more money on such things as treatment for drug and alcohol addiction. He cites his religious faith as motivating him to help those in need. He has said he is open to a path to citizenship for illegal immigrants.

In his first term, he signed a bill to restrict collective-bargaining rights for public employee unions, along the lines of legislation that caused a partisan eruption in Wisconsin under Walker. When Ohio voters rejected the plan in a later ballot initiative, Kasich accepted defeat and has not clashed seriously with unions since over such issues, although he and organized labor have been at odds over spending and taxes.

Now he is entering a Republican presidential field so large that not all of the candidates will be invited onto the stage at the first debate, which will be held Aug. 6 in Cleveland. Fox News Channel, which is hosting that event, has said that only the top 10 candidates, based on a group of national polls, will qualify.

Kasich is in danger of missing the cut for that home-state debate. Advisers hope that his late announcement will give him enough of a bounce to put him in the top 10. Short of that, he will look to become a credible contender in the Granite State.

His supporters think he can connect more effectively than his rivals with his upbeat message and a personality that is direct, occasionally prickly and rarely reserved. Advisers hope that will brand him as authentic at a time of skepticism about canned or programmed politicians.