* Opposition likely to block Calderon's reform bid
* Tensions rising between president and opposition PRI
By Dave Graham and Miguel Angel Gutierrez
MEXICO CITY, June 15 (Reuters) - Mexican President Felipe Calderon urged lawmakers on Wednesday to hold an extra session of Congress in a last ditch effort to push through reforms that the opposition has blocked as it eyes a return to power.
Calderon still hopes to sign off a raft of legislation like a bill to liberalize the labor market as well as a political reform that will for the first time allow independents to run for office and let lawmakers serve consecutive terms.
However, the proposals are unlikely to pass because the lower house of Congress is dominated by the opposition Institutional Revolutionary Party (PRI), which hopes to next year regain the presidency that it held for more than 70 years until 2000.
Taking the unusual step of asking Congress to grant him an extraordinary session, Calderon said the reforms were needed to get the country back on track.
"I want to stress that we're talking about far-reaching changes, transcendent changes, and in many instances, changes that are urgently needed ... to end the inertia that is holding up our development," he said in Mexico City.
But with the presidential vote close, the PRI is seen as unlikely to help Calderon burnish his image, which has been battered by a brutal drugs war and reform deadlock.
"It's like the 14th round in a heavyweight boxing match and Calderon's been knocked down three or four times, and he's woozy and he's staggering around the mat," said George W. Grayson, a Mexico expert at the College of William & Mary in Virginia. "They're not going to do anything that might allow him a resurgence."
Mexico's Congress still has two regular sessions remaining before July 2012, but analysts say the PRI will be focused on the election by the time it reconvenes in September.
Even if Congress were to grant Calderon an extra session, it would be unlikely to fall before three state elections on July 3, all of which the PRI is expected to win.
"So it will be at a time when the wind is behind the PRI, and the PRI is going to be in charge of things," Grayson said.
In recent weeks, Calderon's government has antagonized the PRI -- which holds a big poll lead over his conservative National Action Party (PAN) -- with a spate of arrests of prominent PRI officials, including a former state governor.
The embezzlement investigation into ex-Chiapas governor Pablo Salazar, the arrest of former Tijuana mayor Jorge Hank Rhon and a corruption probe into a close aide of PRI party chairman Humberto Moreira appear to mark the start of a new drive by the PAN to discredit its rival. (Editing by Kieran Murray)