Calcutta, April 17: Mamata Banerjee faces perhaps her biggest test of this Assembly election on its first day, when she is up for what in football parlance may be dubbed an “away game”.

She has been dominating her home territory of south Bengal; tomorrow’s vote will show if she can also conquer the traditional Congress turf of the north. Her problem is that unlike the south where she is fighting only the Left, in the north she is up against her ally too — in the form of “rebel” Congress candidates boosted by the tacit blessing of their regional party bosses.

Mamata is desperate to gain a foothold in the region, and has been promising it goodies in the form of railway projects. In a carefully planned strategy, she has been making frequent trips north of the Ganga to emphasise she is not a “seasonal cuckoo”.

During such a visit in January, she rued that north Bengal had not given her a single MP. Yet, the Trinamul Congress has made undeniable progress in the region over the past couple of years.

Today, the party holds as many as 15 civic seats in Siliguri — the same as the Congress — although it has been forced to sit in the Opposition after the Congress took the Left’s help to form the board following a dispute over the mayor’s post. Trinamul now also has two MLAs from north Bengal, up from zero till a few years ago.