The sight of hundreds of thousands of angry Latinos taking to the streets of American cities, and the prospect of losing the support of the country’s fastest-growing ethnic group for a generation to come, persuaded Republicans to abandon populist plans to send all illegal immigrants home.

With congressional elections looming in November, Democrat and Republican leaders instead agreed the basis of a compromise after weeks of bitter dispute over immigration reform.

This is expected to restrict the flow of new arrivals and give seven million undocumented workers who have lived in the US for more than five years the right to apply for citizenship, provided they pay fines and taxes and learn English.

Three million others will be asked to go home before returning on temporary work visas that could ultimately qualify them for citizenship. About a million who have been in America for fewer than two years will be required to leave and then “wait in line” for permits.

Most Republicans had previously supported hardline legislation approved by the House of Representatives in December that made it a federal felony to live illegally in the US.

But for all the daily antiimmigration rants of right-wing broadcasters about “broken borders”, a wave of protests in recent weeks has forced even Republican hardliners to think again. About 500,000 demonstrators took to the streets of Los Angeles a fortnight ago, 100,000 marched in Chicago and many more protested in cities from New York to Denver. A huge crowd was expected at the Washington Monument on Monday.

Spanish-speaking radio stations and Catholic and evangelical churches have been busy galvanising the Latino community like never before. Thousands of Hispanic youths have staged walkouts at schools, some of which have banned the Mexican flag to ease tensions.

“The sleeping Latino giant is finally awake,” said Jaime Contreras, president of the national Capital Immigration Coalition.

Lindsey Graham, a Republican senator, said over the weekend: “This is a defining moment for the Republican Party. If our answer to the fastest-growing demographic in this country is that ‘we want to make felons of your grandparents and we want to put people in jail who are helping your neighbours and people related to you’, then we’re going to suffer mightily.”

Senator John McCain, a front-runner for the next Republican presidential nomination who had co-sponsored legislation to allow immigrants a chance to become citizens — with the Senate’s arch liberal, Edward Kennedy — suddenly found himself less isolated as colleagues began looking nervously toward the elections.

Ed Gillespie, the former Republican National Committee chairman and a White House ally, similarly urged his party to resist the siren voices of anti-immigration rhetoric. Business leaders who do not want to lose the supply of cheap immigrant labour also weighed into the argument.

Hispanic voters represent about 12.5 per cent of the US electorate, a proportion which is rising fast and is already higher than that for black people. Karl Rove, the senior strategist to President Bush, identifies these voters as proto-Republicans who usually have socially conservative views despite being left of centre on economic issues.

Mr Bush has remained vague on the issue, saying he wanted a Bill that recognised that America had been built by immigrants, while stopping short of an automatic amnesty for illegal workers. Yesterday, he merely said he was “pleased” that there was now a prospect of getting a “comprehensive immigration Bill agreed”.

While a last-minute hitch remained possible, both sides appeared optimistic last night that agreement could be reached. Jeb Bush, his brother and the Governor of Florida, said this week that the sight of “politicians pounding their chests about immigration” was hurtful for both him and his Mexican-born wife.

But Bill Frist, the Senate Majority Leader, declared that a “huge breakthrough” had been made. Harry Reid, the Democratic minority’s leader, said: “Let’s stop the name-calling and let’s stop the polemics. We’re working together for Americans and for people who yearn to be Americans.”

HUMAN TIDE

Times Recommends

• Swiss back free-heroin scheme for addicts
• Young gymnasts risking a life of pain
• Defiant café shows Mumbai is not afraid