Mitt Romney inched closer to secure Republican party's nomination to challenge President Barack Obama in November with victories in three party primaries in Indiana, North Carolina and West Virginia.

With no serious competition, Romney was able to collect the bulk of the 100 or so delegates at stake in Tuesday's primaries on his way to the party's official nominating convention in Tampa, Florida at the end of August.

The former Massachusetts governor now has 934 of the 1,144 delegates needed to secure the nomination, according to CBS News estimates.

While his closest rival former Pennsylvania senator Rick Santorum gave up his run for the White House last month, former House speaker Newt Gingrich dropped his bid for the presidency last week.

But House member Ron Paul, who has thus far garnered an estimated 92 delegates, still remains in the race.

According to the latest polls, Obama and Romney are in a tight race for the White House.

In a Gallup/USA Today poll of 12 swing states released this week, Obama edged out Romney 47 percent to 45 percent.

The result is within the poll's four-point margin of error and closer than Gallup's last swing state poll from March, when Obama held a nine-point lead.

On the critical issue of the economy, Romney has the advantage: In a direct comparison, 47 percent said Romney would do a better job managing the economy, while 44 percent said Obama would.

As many as 60 percent said Romney would do a good job or very good job as president handling the economy over the next four years, while 52 percent said the same about Obama.

(Arun Kumar can be contacted at arun.kumar@ians.in)