WASHINGTON, May 3 (Xinhua) — U.S. Republican candidate Donald Trump has virtually secured the nomination with a win in Indiana Tuesday night, and experts say he could even beat likely Democratic nominee Hillary Clinton in the presidential race if he can tone down his explosive rhetoric.

The brash businessman cruised to an easy win in Indiana, which forced his chief rival Senator Ted Cruz to quit his campaign.

While many analysts only six months ago dismissed Trump as a flash in the pan, they simply underestimated the level of public anger over the weak U.S. job market and bitterness against Washington insiders.

While Trump has a high negative rate — the rate at which people dislike a candidate — those of Clinton are nearly as high, as a number of Americans find her stiff and unapproachable, and see her as someone who does not understand the needs of ordinary Americans.

But perhaps the most telling is that Clinton has failed to galvanize her party or excite her supporters in the same way as Trump has done.

This has been shown by strong Democratic support for rival Senator Bernie Sanders, who put up a tough fight against Clinton over the past several months, despite Clinton just six months ago being considered a shoo-in for the nomination.

Sanders is expected to stay in the nomination race longer after his win in Indiana Tuesday night.

For a virtual unknown — and a socialist at that, a philosophy seen by many as un-American — to gain so much enthusiasm from voters demonstrates that Clinton is a weak candidate, many analysts believe.

Despite being a celebrity outside the United States, Clinton, the former first lady and secretary of state, simply neither excites nor galvanizes her base.

In sharp contrast, after Trump steamrolled through the states of Maryland, Connecticut, Delaware, Pennsylvania and Rhode Island last week, he has momentum on his side.

Some analysts now say that the only one who can beat Trump is Trump himself — while he has galvanized the Republican rank and file like no other Republican candidates in recent years, he is also vehemently disliked by many outside his base.

Republican strategist Ford O'Connell told Xinhua that if Trump just adjusts his rhetoric a bit to be less offensive, "he could actually win this thing."

"The tone and rhetoric is a major problem," he said.

"He only needs to do a combined 600,000 votes more than Romney did in four to five states. And if he does that he's the next president of the United States," O'Connell said, referring to former Republican nominee Mitt Romney's 2012 White House run.

Trump has in fact quickly changed his tone after the Indiana win. In his victory speech in New York, he already praised his rival Cruz, who he used to call "Lying Ted," as "a tough, smart guy" who "has got an amazing future."

Still, there is the burning question of Hispanic voters. The Hispanic vote is particularly worrisome for Trump, as he is strongly disliked by many in this crucial voting bloc after calling Mexican immigrants "rapists" and vowing to build a wall to keep out illegal immigrants from Latin America.

However, if Trump chooses former Republican candidate Marco Rubio — the son of Cuban immigrants — as a running mate, the Florida senator could help Trump gain enough Hispanic votes to clinch the presidency, experts say.

O'Connell said Trump would just need around 30 percent of the Hispanic vote to win the White House, adding that Rubio's Spanish language skills would also help smooth over Trump's image with Latino voters.

"Rubio speaks fluent Spanish, which means he could take on Spanish-language media (in the United States) and try to smooth over some perception issues," he said.

If Trump teams up with Rubio, he will have a shot at winning Florida, the crucial state that plays a major role in U.S. general elections, O'Connell added.