NEW DELHI — Two years ago, Narendra Modi would have imagined a very different 2019 election campaign awaiting him.

He would have expected his dominance on the national stage to continue until the start of the year, ahead of the spring general elections. He would have foreseen his chief ally, BJP party leader Amit Shah, operating machine politics with the granular grasp of India's demography to inexorably drive Modi to a second term in power. The cloying and pliable section of the media would be egging him on, the opposition would be in disarray and corporate figures would not have the nerve to envisage a government without him, and plan accordingly.

Every element of that rosy scenario has now come unstuck for Modi. The opposition is organizing and swiftly tapping into the disaffection with his government. Rahul Gandhi has come into his own over the last year and has got the better of Modi in just about every measure of political combat. He has won three major state elections, his social media engagement levels are way ahead of Modi despite the latter's larger following. More importantly, Rahul Gandhi has set the pace in political rhetoric through speeches, one-liners and tweets. Modi is, meanwhile, grasping for a story to tell — promised jobs have not materialized, rural India is seething and the country is exhausted with the slash and burn mode of governance that has come to typify BJP rule.

And now Priyanka Gandhi Vadra has stepped with two feet into politics, further complicating matters for Modi. With just 100 days until the elections, choreography matters. Priyanka will, alongside her older brother Rahul, suck up some oxygen of publicity and attention that Modi has come to take for granted.

Worse, she comes in at a time when he's already overexposed and bereft of new tricks. He and the BJP have tried everything to establish dominance: an upper caste quota, demonetization, selfies with celebrities, attacks on Muslims, media, activists and students. His ability to surprise is fading. The opposition is uniting, there's no money in the treasury to buy off voters, conflict with Pakistan is not imminent — and will be expensive. Modi's act remains the same; India is moving on.

Rahul Gandhi has virtually been handling everything himself.

All that is left to fight for is political combat itself, which the BJP is good at through its polarizing tactics. Priyanka potentially adds a new dynamic to this. While the BJP continues with its unsavory, hateful rhetoric, Rahul will try and extend in the public's mind the decency gap that he has established between himself and the Modi-Shah duo, while Priyanka, in theory, gets into the more dramatic cut and thrust of politics. The Gandhis will now hunt in pairs in a media environment that is no longer entirely in Modi's control.

There will also be a measure of burden sharing. Rahul Gandhi has virtually been handling everything himself — rebuilding his brand, generating momentum for criticism of last year's Rafale fighter jet deal and responding to criticism from Amit Shah and company. No other Congress heavyweight or regional party leader has confronted Modi with the regularity or impact that Rahul has — or been the singular focus of their backlash. Priyanka has now stepped in to take on Modi, Shah and the others. All this will make for great theater for the middle class and galvanize the Congress party more broadly.

The BJP will hope that the novelty of the news passes quickly so it can normalize Priyanka and represent her as just another Indian politician with a dynastic name. This won't be easy. A hundred days are not enough. Besides, she has presence, communicates well in both English and Hindi and, being skeptical of the media, will likely deal with it on her terms.

It's worth noting how astutely Rahul and the Congress set up her entry into politics. The party waited for Rahul's political identity to develop, to consolidate his habit of cultivating audiences at home and abroad, for him to win three state elections on his own — so there is no hint that Priyanka made the difference (nor rumors emerge of brother-sister factions in the party).

Priyanka Gandhi's foray into politics seems principally about the atmospherics of the election to follow and the ability of that theater to regain the support of groups that the Congress party has lost in recent years. The Congress needs to tread warily in this endeavor, and Rahul and Priyanka have the task of tapping into disenchantment with Modi, without alienating historic allies or handing the BJP easy wins.

Sushil Aaron is a commentator on India's politics and international affairs. He tweets @SushilAaron