The Lok Sabha electoral battle, that had begun on April 11, has finally reached the country's commercial capital of Mumbai in its fourth phase. The six constituencies of Mumbai are among 17 from across Maharashtra that will see polling on Monday.

In 2014, the BJP-Shiv Sena alliance had won all six Lok Sabha seats in Mumbai, while the Congress-NCP combine had done the same feat in 2009. All six seats are, however, expected to have a neck and neck contest again this time and the renewing of several old contests. Both Congress-NCP and BJP-Shiv Sena alliances are hoping to come up triumphant.

Milind Deora, who had won Mumbai South in 2009 before losing it to Sena's Arvind Sawant in 2014, will again face his bete noire, while Sena MP Rahul Shewale is again pitted against Congress's ex-MP Eknath Gaikwad in Mumbai South Central. In Mumbai North West, where the swing of Marathi voters will be crucial, the daughters of two senior party leaders are up against each other. Priya Dutt of Congress is fighting against BJP MP Poonam Mahajan from this seat.

In Mumbai North, the star power of Congress candidate Urmila Matondkar will be tested when she comes up against BJP's heavyweight MP Gopal Shetty.

In Mumbai North East, Sanjay Dina Patil of NCP had lost to BJP's Kirit Somaiya in 2014, but the saffron party surprised the city by fielding newcomer Manoj Kotak from the constituency this time. And finally, from Mumbai North West, Congress's ex-MP Sanjay Nirupam is fielded against Sena MP Gajanan Kirtikar. In all six seats, Maharashtrian and North Indian voters are likely to play a crucial role.

Another factor that will play a crucial role is the voter turnouts in the city. Mumbai has historically suffered poor voter turnouts, and psephologists will be keenly watching to see if it can buck the trend this time. In 1999, the city had just a 45 per cent voter turnout, which it improved to 47.30 per cent five years ago. However, in 2009, things plunged further, when there was just a 41.40 per cent turnout. Five years ago, in 2014, Mumbai had a revival of sorts, when 53 per cent voters exercised their franchise.

In addition, the fourth phase of polling will also visit eight other states, covering 71 seats in all. This includes Anantnag in Jammu and Kashmir, which is having a multi-phase polling in the same constituency, for the first time in India. Elaborate security arrangements have been made for polling in Anantnag, and on Monday, over 3.45 lakh voters are expected to exercise their franchise in Kulgam district.

In Uttar Pradesh, 2.38 crore people will exercise their franchise, including Samajwadi Party president Akhilesh Yadav's wife Dimple Yadav, while in Rajasthan, Chief Minister Ashok Gehlot's son Vaibhav is fighting from Jodhpur.

One of the more interesting fights will be in Bihar's Begusarai district, where the CPI has fielded Kanhaiya Kumar, one of the accused in the JNUSU sedition case, who is taking on Union minister Giriraj Singh.

In West Bengal, the fate of 68 candidates is in the balance, spread over eight seats. Most of these will see a four-cornered contest between the Trinamool Congress, BJP, Congress and the Left Front.

In Madhya Pradesh, polling will take place at six Lok Sabha seats, although all eyes will be on Chhindwara, considered Chief Minister Kamal Nath's bastion, from where his son Nakul Nath is fighting this time. The fourth phase of polling will be the last for Odisha, and over 95.14 lakh voters can exercise their franchise to decide the fate of 52 candidates here.

Voting has already taken place for 302 seats, while 71 more will be decided on Monday. The fifth phase will be on May 6, followed by a sixth phase on May 12 and the final phase on May 19. Counting of all votes will be held on May 23.