Washington: Republican presidential front-runner Donald Trump is leading with an impressive margin in the key state of Florida while he is in a virtual tie with his opponent John Kasich in Ohio, a latest poll said on Sunday ahead of the Tuesday's primaries.
Hillary Clinton, the Democratic presidential front-runner, on the other hand appears to be cruising towards being the party's nominee for the November 8 elections, as latest polls showed she was leading in Florida and Ohio, but trailed in Illinois.
The polls came as White House aspirants on both the Republican and Democratic parties intensified their campaigning ahead of the Tuesday's primaries in Florida, Illinois, Missouri, North Carolina and Ohio.
Except for North Carolina, the delegates would go to one candidate ? the winners of the primary in the states.
Releasing details of its polls, CBS news said that Trump (44 per cent) has a 20 per cent lead over Ted Cruz (24 per cent) and Marco Rubio (21 per cent) in Florida where 99 delegates are at stake.
Florida is the home state of Rubio, who has been campaigning here for the past few days.
A loss here would virtually end the presidential campaign of Rubio, who so far has won only three primaries in Minnesota, Puerto Rico and Washington DC.
He has 163 delegates so far as against 370 of Cruz and 460 of Trump.
In Ohio where 66 delegates are at stake, Trump and the popular State Governor John Kasich are headed for a very tight finish, CBS polls said, adding that both have support of 33 per cent of the prospective Republican primary goers.
Kasich who has just 63 delegates to his kitty and has not won even a single state so far, Ohio is a "must-win-state" for him to stay in the race to the White House.
In Illinois where 69 delegates are at stake in winner-take-all primary, Trump is leading ahead of Cruz.
On the Democratic side, Clinton seems to have an edge over her sole rival Bernie Sanders in the Tuesday's primaries.
Clinton leads Sanders by 28 points in Florida, 62 to 34 percent, and by nine points, 52 to 43 percent in Ohio as per the CBS News Battleground Tracker poll.
However, Sanders leads Clinton very narrowly in Illinois 48 to 46 per cent, it said.
While Sanders is giving an unexpected tough fight to Clinton, the former Secretary of State is way ahead of the Vermont Senator in the count of delegates.
To bag Democratic party's presidential nomination, a candidate needs 2382 of the 4763 delegates.
Clinton so far has 1231 delegates which includes 748 from the Democratic primaries and 465 super delegates, meaning party's leadership.
Sanders has 576 delegates which includes 542 from the primaries and has support of just 25 super delegates.
Super delegates can change their position later on. The delegates from both the Republican and Democratic parties would meet later this summer at the once-in-four-year conventions in Cleveland and Philadelphia respectively where they would formally elect their presidential nominee.
Those candidates having majority of the delegates would be elected as the party's presidential nominee.